Data for paper: Single-molecule Magnet Properties of Silole- and Stannole-ligated Erbium Cyclo-octatetraenyl Sandwich Complexes

X-ray crystallography data for all compounds in .cif format.check_cif files for all compounds.FTIR data for all compounds.NMR data for stannole.Raw magnetic data in .dat format.AbstractThe synthesis, structures and magnetic properties of an η5-silole complex and an η5-stannole complex of erbium are reported. The sandwich complex anions [(η5-CpSi)Er(η8-COT)]– and [(η5-CpSn)Er(η8-COT)]–, where CpSi is [SiC4-2,5-(SiMe3)2-3,4-Ph2]2– (1Si), CpSn is [SnC4-2,5-(SiMe3)2-3,4-Me2]2– (1Sn) and COT = cyclo-octatetraenyl, were obtained as their [K(2.2.2-cryptand)]+ salts and found to be isostructural, with remarkably similar bond lengths and angles, differing only in the lengths of the Er–E interactions (E = Si, Sn). The parallels in the molecular structures of 1Si and 1Sn are reflected in their dynamic magnetic properties, which show single-molecule magnet behaviour in zero applied field, with effective energy barriers of 115 ± 7 and 125 ± 3 cm–1, respectively, along with comparable magnetic relaxation times. Analysis of the two complexes using ab initio calculations reveals differences at a quantitative level, but overall similar electronic structures, with the thermally activated relaxation likely to proceed via the first-excited Kramers doublet. Comparing 1Si and 1Sn with the previously reported germanium analogue 1Ge reveals that swapping one heavier group 14 element for another in complexes of the type [(η5-CpE)Er(η8-COT)]– has a minimal impact on the SMM behaviour.本数据集包含所有化合物的X射线晶体学（X-ray crystallography）数据，格式为.cif，请核查所有化合物的.cif文件。所有化合物均配有傅里叶变换红外（FTIR）数据，同时包含锡杂环戊二烯（stannole）相关化合物的核磁共振（NMR）数据。原始磁学数据格式为.dat。 摘要：本文报道了铒的η⁵-硅杂环戊二烯（silole）配合物与η⁵-锡杂环戊二烯（stannole）配合物的合成、结构及磁学性质。所获得的夹心型阴离子配合物[(η⁵-CpSi)Er(η⁸-COT)]⁻与[(η⁵-CpSn)Er(η⁸-COT)]⁻以[K(2.2.2-穴醚(2.2.2-cryptand))]⁺盐的形式分离得到，其中CpSi为[SiC₄-2,5-二(三甲基硅基)-3,4-二苯基]²⁻（1Si），CpSn为[SnC₄-2,5-二(三甲基硅基)-3,4-二甲基]²⁻（1Sn），COT为环辛四烯基（COT）。两种配合物为同构体，键长与键角极为相近，仅在Er-E相互作用（E=Si、Sn）的键长上存在差异。1Si与1Sn的分子结构相似性同样体现在动态磁学性质上：二者在零外场下均表现出单分子磁体行为，有效能垒分别为115 ± 7 cm⁻¹与125 ± 3 cm⁻¹，且磁弛豫时间相当。通过从头算（ab initio calculations）对两种配合物进行分析发现，二者在定量层面存在差异，但整体电子结构相似，热激活弛豫过程大概率经由第一激发态克莱默二重态（Kramers doublet）进行。将1Si、1Sn与此前报道的锗类似物1Ge进行对比可知，在[(η⁵-CpE)Er(η⁸-COT)]⁻型配合物中，将第14族的一种重元素替换为另一种重元素，对其单分子磁体行为的影响极小。